4,722 research outputs found
Numerical study of two-dimensional moist symmetric instability
The 2-D version of the non-hydrostatic fully compressible model MOLOCH developed at ISAC-CNR was used in idealized set-up to study the start-up and finite amplitude evolution of symmetric instability. The unstable basic state was designed by numerical integration of the equation which defines saturated equivalent potential vorticity q<sub>e</sub><sup>*</sup>. We present the structure and growth rates of the linear modes both for a supersaturated initial state ("super"-linear mode) and for a saturated one ("pseudo"-linear mode) and the modifications induced on the base state by their finite amplitude evolution
Structural studies of mesoporous ZrO-CeO and ZrO-CeO/SiO mixed oxides for catalytical applications
In this work the synthesis of ZrO-CeO and
ZrO-CeO/SiO were developed, based on the process to form
ordered mesoporous materials such as SBA-15 silica. The triblock copolymer
Pluronic P-123 was used as template, aiming to obtain crystalline single phase
walls and larger specific surface area, for future applications in catalysis.
SAXS and XRD results showed a relationship between ordered pores and the
material crystallization. 90% of CeO leaded to single phase homogeneous
ceria-zirconia solid solution of cubic fluorite structure (Fmm). The
SiO addition improved structural and textural properties as well as the
reduction behavior at lower temperatures, investigated by XANES measurements
under H atmosphere
Spectral and Spatial Dependence of Diffuse Optical Signals in Response to Peripheral Nerve Stimulation
Using non-invasive, near-infrared spectroscopy we have previously reported optical signals measured at or around peripheral nerves in response to their stimulation. Such optical signals featured amplitudes on the order of 0.1% and peaked about 100 ms after peripheral nerve stimulation in human subjects. Here, we report a study of the spatial and spectral dependence of the optical signals induced by stimulation of the human median and sural nerves, and observe that these optical signals are: (1) unlikely due to either dilation or constriction of blood vessels, (2) not associated with capillary bed hemoglobin, (3) likely due to blood vessel(s) displacement, and (4) unlikely due to fiber-skin optical coupling effects. We conclude that the most probable origin of the optical response to peripheral nerve stimulation is from displacement of blood vessels within the optically probed volume, as a result of muscle twitch in adjacent areas.National Institutes of Health (R01-NS059933); U.S. Army Medical Acquisition Activity (W81XWH-07-2-0011
Numerical study of a banded precipitation event over Italy
Satellite images of 30 October 2008 show the development
over north-central Italy of rainbands and multiple
waves during a strong south-westerly wind episode
associated with a deepening synoptic trough and
cold front passage.
The event was studied by means of the ISAC model chain constituted
of the hydrostatic model BOLAM and the nested non-hydrostatic model
MOLOCH at 1.1 km resolution.
Diagnostics of model output was performed to reveal the
physical origin of the dynamical features and precipitation
field as simulated.
Based on our results we propose a theoretical framework in
which symmetric instability underlies some of the observed
precipitation patterns
Numerical study of a banded precipitation event over Italy
Satellite images of 30 October 2008 show the development
over north-central Italy of rainbands and multiple
waves during a strong south-westerly wind episode
associated with a deepening synoptic trough and
cold front passage.
The event was studied by means of the ISAC model chain constituted
of the hydrostatic model BOLAM and the nested non-hydrostatic model
MOLOCH at 1.1 km resolution.
Diagnostics of model output was performed to reveal the
physical origin of the dynamical features and precipitation
field as simulated.
Based on our results we propose a theoretical framework in
which symmetric instability underlies some of the observed
precipitation patterns
In vitro and in vivo inhibition of breast cancer cell growth by targeting the Hedgehog/GLI pathway with SMO (GDC-0449) or GLI (GANT-61) inhibitors.
Aberrant Hedgehog (Hh)/glioma-associated oncogene (GLI) signaling has
been implicated in cancer progression. Here, we analyzed GLI1, Sonic Hedgehog
(Shh) and NF-κB expression in 51 breast cancer (ductal carcinoma) tissues using
immunohistochemistry. We found a positive correlation between nuclear GLI1
expression and tumor grade in ductal carcinoma cases. Cytoplasmic Shh staining
significantly correlated with a lower tumor grade. Next, the in vitro effects of two
Hh signaling pathway inhibitors on breast cancer cell lines were evaluated using the
Smoothened (SMO) antagonist GDC-0449 and the direct GLI1 inhibitor GANT-61.
GDC-0449 and GANT-61 exhibited the following effects: a) inhibited breast cancer
cell survival; b) induced apoptosis; c) inhibited Hh pathway activity by decreasing
the mRNA expression levels of GLI1 and Ptch and inhibiting the nuclear translocation
of GLI1; d) increased/decreased EGFR and ErbB2 protein expression, reduced p21-
Ras and ERK1/ERK2 MAPK activities and inhibited AKT activation; and e) decreased
the nuclear translocation of NF-κB. However, GANT-61 exerted these effects more
effectively than GDC-0449. The in vivo antitumor activities of GDC-0449 and GANT-
61 were analyzed in BALB/c mice that were subcutaneously inoculated with mouse
breast cancer (TUBO) cells. GDC-0449 and GANT-61 suppressed tumor growth of
TUBO cells in BALB/c mice to different extents. These findings suggest that targeting
the Hh pathway using antagonists that act downstream of SMO is a more efficient
strategy than using antagonists that act upstream of SMO for interrupting Hh signaling
in breast cancer
Raman excitation spectroscopy of carbon nanotubes: effects of pressure medium and pressure
Raman excitation and emission spectra for the radial breathing mode (RBM) are
reported, together with a preliminary analysis. From the position of the peaks
on the two-dimensional plot of excitation resonance energy against Raman shift,
the chiral indices (m, n) for each peak are identified. Peaks shift from their
positions in air when different pressure media are added - water, hexane,
sulphuric acid - and when the nanotubes are unbundled in water with surfactant
and sonication. The shift is about 2 - 3 cm-1 in RBM frequency, but
unexpectedly large in resonance energy, being spread over up to 100meV for a
given peak. This contrasts with the effect of pressure. The shift of the peaks
of semiconducting nanotubes in water under pressure is orthogonal to the shift
from air to water. This permits the separation of the effects of the pressure
medium and the pressure, and will enable the true pressure coefficients of the
RBM and the other Raman peaks for each (m, n) to be established unambiguously.Comment: 6 pages, 3 Figures, Proceedings of EHPRG 2011 (Paris
Couples living with type 1 diabetes : an integrative review of the impacts on health and wellbeing
Impacts of type 1 diabetes and relationship factors on health and wellbeing of both persons with diabetes and partners (T1D partners) have not been investigated. Integrative review methods evaluated the evidence. From 323 titles, we included 24 studies involving 16,083 persons with diabetes and 1020 T1D partners. Studies were quantitative (n = 13), qualitative (n = 9) and mixed methods (n = 2). Maintaining resilient, good quality, intimate relationships optimises physical and psychological outcomes for persons with diabetes. Partners experience disturbed sleep and while general psychological health is maintained, distress surrounding hypoglycaemia is overwhelming for over a third of partners. Nurturing quality relationships could reap significant health benefits
Secondary forest succession in the Mata Atlantica, Brazil: floristic and phytosociological trends.
This study aimed at understanding the dynamics of ecological processes and the use of secondary forests in Santa Catarina state (Brazil). The data base for these studies was formed through forest inventories carried out in the three forest types of the state. The results of this study demonstrate that the patterns of diversity are very similar among the three forest types; however, the species compositions among the types are quite different. A total of 343 woody species belonging to 73 families were found in the 24,000 m2 sampling area, revealing the potential role of secondary forest in the conservation of biodiversity at the landscape scale. As expected, a small set of pioneer species dominates young secondary forests with shade-tolerant species becoming structurally important after 30 years. The patterns of forest structure and species diversity observed in study largely conform to the postagricultural secondary succession observed for many tropical forests.Article ID 759893
- …
